Process for the production of useful fuel gas



' Nov. 17,1942. I F, -TQTZEK 2,302,157

' PROCESS FOR THE PRODUCTION OF USEFUL FUEL GAS Filed May 20. 1940 3Sheets-Sheet l I F. To riE 2,302,157

Nov. 17, 1942.

PROCESS FOR THEV PRODUCTION OF USEFUL FUEL GAS Filed May 20, 1940 3Sheets-Sheet 2 L 11: SK 1 A? 31. IL: KIM: If E 1i; 1 I m 1 m u m u m 4Nov. 11,1942. TOTZEK 2,392,157

I PROCESS FOR THE PRODUCTION OF USEFUL FUEL GAS' Filed May 20, 1940 sSheets-Sheet 3 I Patented Nov. 17, 1942 rlJNlTED s ArEs PATENT O I2,302,137

raocass FOR 'rnn raonUcrroN or USEFUL roar. ass I Application May 20,1940, Serial no. 336,125

In Germany May 31, 1939 4 Claims. (01. 43-203) In my copendingapplication for Letters Patent relating to improvements in a'process forthe production of useful fuel gas, executed on the 30th day of April,1940, Serial No. 336,124, filed May 20, 1940, a process is disclosed forthe production of fuel gas of high calorific value out of dusty orfinely granular fuels, such as black or brown coal, or coke andsemi-coke made therefrom, by the conversion of the solid carbonaceousfuel at high temperature with steam and carbon dioxide and oxygen, thefuel in suspension being brought into contact with hot gases containingcarbon dioxide, said gases being made by the combustion of part of thegas produced, and the hot mixture consisting of gas and fuel is treatedwith steam.

In order to obtain a good yield of valuablefuel gas of a high calorificvalue, it is necessary to keep the temperature of the media within thegas producer as high as possible. In case the useful gas produced ispartly used for heating purposes, the necessary high reactiontemperature 7 can only be arrived at if the heating media (combustionair and fuel gas) are preheated to a sufficiently high degree.

The present invention, which has for its aim to obtain a simple andefflcient preheating of the heating media in connection with the processaccording to my above mentioned patent application, now provides forpreheating regeneratively the heating media serving for the productionof hot reaction gases, and to conduct the waste gases generated by thecombustion of thehighly preheated heating media partly as reaction gasthrough the gas producer and partly through another regenerative gasheater which serves to store the sensible heat from this partial streamof waste gases and later to preheat the heating media in anotheroperating period of the regenerator.

Furthermore,'the regenerative gas heater which is used for preheatingthe heating media may be employed to preheat the steam which is shitabLvadded either to the combustion air or to the fuel gas or to both themedia in an adjustable manner. By the combustion of the preheatedheating media in the presence of steam it is possible to keep thecombustion temperature exactly at the desired degree so as to avoiddangerous superheatings which may occur under certain conditions whenhighly preheated material is burnt.

Another object of this invention is to introduce the hot mixture ofcombustion gases containing carbon dioxide and steam through openingsinto the gas producer, a partial stream beingpreferably introduceddirectly at the inlet of fuel dust in such a manner that the fuel dustis distributed most favourably within the reaction chamber.-

With the above and other objects and features of my present invention inview, I shall now describe a preferred embodiment thereof on the linesof theaccompanying drawings, in which:

Figure 1 is a vertical section of a gas producer built according to myinvention.

Figure 2 is a horizontal section on line II-II of Fig. 1.

Figure 3 is a vertical section on line III-III of Fig. 2 and Fig.4 is ahorizontal section through the re-' generative gas heater on line IV--IVof Fig. 3.

- The apparatus shown on the drawings consists of a gas producer chamberI having substantially the shape of a horizontal cylinder, said gasproducer chamber being formed by a suitable Jacket 2 made of refractorybrickwork 3. At the one end of the reaction chamber I, preferably nearthe axial front end wall 4, a fuel delivery opening Bis provided towhich suitable feeding means outside chamber I are connected which meansare not shown on the drawings for simplicitys sake.

In the walls of the gas producer chamber I either only in the lower halfof the gas producer chamber as shown in Fig. 1 or distributed over thewhole area of same, there is arranged a series of nozzle-like openings 6which terminate into the gas producer chamber I not completelytangentially: The nozzle openings I extend from the ring-like orcircumferential distributing channels I situated inthe brickwork 3. Thering-dike channels I are connected to a common connecting channel 8 fromwhich leads a chan- .nel 9' to a combustion chamber III in which areproduced 'the hot combustion gases containing carbon dioxidenecessary-for the gasifyins Process. The combustion chamber ill isformed as a U-shaped channel connected at each end to a tower-like gasheater II, I2. In each of the gas heaters I I and I2 are formed twoseparate compartments III, I! and I6, I! by central partition walls I3.These gas heater compartments are filled with chequerwork in the wellknown manner which serves for the heat exchange between the media whichtransfer and take up the heat.

At the bottom of the gas heater compartments are openings I8, I9, 20,2i. These openings are controlled each by a suitable shut-oil valve 22(see Fig. 1) to which are connected outside the pipe lines 23 leading tothe waste gas collecting channel 24 which communicates with the stack.Moreover the gas heater compartments are equipped with openings 25, 2B,21, 28 (see Fig. 2) which are arranged at the bottom and serve for theintroduction of the media to be heated into the gas heaters.

The working method of the contrivance shown on the drawings is asfollows:

It is assumed that the gas heater compartments H and I5 are to serve toheat up the heating media. In this case the openings 18 and it areclosed by manipulating the corresponding shutoiI valves 22 and the pipelines 25, 28 are opened so that the combustion air may enter from belowinto the gas heater compartment I4 and fuel gas into the gas heatercompartment IS. The media flowing upwards through the gas heatercompartments ll, I! thus absorb heat from the chequerwork which had beenheated up in the preceding operating period. The heated media then leavethe gas heater compartments I 4 and i5 at the upper end and mix withinthe one leg of the U-shaped combustion chamber I where the combustiontakes place. The combustion chamher It is suitably dimensioned in such amanner that the combustion may be completed there.

Part of the hot gases produced then flows through the channel 9 and theadjacent connecting channel 8 into the distributing channels 1 of thegas producer from where they enter.

through the openings 6 into the gas producer chamber I. The openings 6.are arranged in such a way that a spiral-like movement iseffected withinthe gas producer by means of which the gases flow gradually from thefront wall 4 where is situated the fuel inlet to the other front wall inwhich is disposed the outlet 29 for useful gas. Finely granular or dustyfuel is sprayed through the opening 5 into the gas producer chamber. Thefuel dust falling through the opening 5 into the gas producer chamber istaken up by a partial stream of hot media which is introduced throughthe remote opening 20 into the gas producer chamber l. The opening 30 issituated in front of the fuel dust inlet 5 in direction to direct astream of gas into the fuel from 5 so that the fuel dust, in welldistributed form, is added to the gases passing through the gas producerchamber from the openings 8.

Steam is added through special channels or it is I added 'to the mediaflowing through the opening 6 into the gas producer chamber I. The steammay be introduced with one or both the heating media into the-gas heaterso that the combustion takes place within the chamber Iii in thepresence of steam.

Part of the hot waste gases produced in the combustion chamber I0 is ledthrough the other end of the U-shaped chamber In intothe'regeneratorcompartments l5, l1. During this operating period, thegas heater. compartments l5, l1

are in connection with the waste heat flue 24 by means of openings '20,2|. The openings 21,

28 of the gas heater compartments I6, II are closed during this period.

As soon as the gas heater H is cooled down, the heating direction isreversed i. e. the gas heater [2 which has just been heated up duringthe preceding operating period is now used for preheating the heatingmedia and the gas heater H is heated up anew by a partial stream of thehot combustion gases.

asoa ev 1. In a process for the production of fuel gas of high calorificvalue from dusty or finely granular fuels, such as black or brown coal,or coke or semi-coke made therefrom, by the conversion of thecarbonaceous fuel at high temperature with steam and carbon dioxide,which comprises: contacting the fuel to be treated with hot combustiongases and steam in a conversion zone to convert them to fuel gas rich inhydrogen and carbon monoxide: effecting combustion of fuel gas and airin a combustion zone apart from the carbonaceous conversion zone;flowing fuel gas and air in alternation through preheated regenerativeheat exchange media of one and then the other of two sets of separateregenerative heat exchange media for fuel gas and air and therebypreheating the gases to be used in the combustion step to provide hotcombustion gases with acother of the'two sets, and thereby heating upthe heat exchange media of the respective sets in alternation forpreheating of the gases for the combustion zone during the nextregenerative operating period of the process.

2. A process as claimed in claim 1 and in which the steam for use in theconversion in the which the steam and hot combustion gases for theconversion zone are introduced in mixture into contact with thecarbonaceous fuel in the conversion zone as a semi-circumferentialseries of jets and in such manner as to impart a spiral like currentmovement to the hot gas and carbonaceous fuel during their contact inthe conversion zone.

4. A process as claimed in claim 1, and in which the steam and hotcombustion gases for the conversion zone are introduced in mixture intocontact with the carbonaceous fuel in the conversion zone as asemi-circumferential series of jets at a region remote from the regionat which the carbonaceous fuel'is introduced into the conversion zoneand in such manner as to impart a spiral like current movement to thehot gas and carbonaceous fuel during their contact in the conversionzone and in which another portion of the hot combustion gas is let intothe conversion zone directly in front of the fuel being introduced so asto setthe fuel into spiral motion in the conversion zone in advance ofits contact with the semi-circumferential series of jets of hotcombustion gas.

FRIEDRICH TO'I'LEK

